Hello @Cristiano Degiorgis,
Thank you for reaching Microsoft!
By utilizing the Graph event API, I can retrieve the recurrence details for Yearly pattern types. Kindly refer to the attached response screenshot for verification. I recommend confirming the ID of the event you are attempting to retrieve through the Graph API. Additionally, ensure that the responses from the Graph API are being processed correctly in your application or connectors.
Documentation Reference: https://learn.microsoft.com/en-us/graph/outlook-schedule-recurring-events?source=recommendations
Hope this helps.
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